Peter Ciaccia has been running marathons, in one form or another, for decades.

The race director of the TCS New York City Marathon will retire after spearheading the annual event for 15 years.

Though his official involvement began in 2001, Ciaccia ran with the organization for many years, and he even participated in several marathons. Prior to working for New York Road Runners, Ciaccia had a successful career in the entertainment industry.

“It was a point in my life, at that time, where I was looking for something to do, a career change,” he said.

After completing the marathon, Ciaccia started talking to Mary Wittenberg, NYRR’s former CEO, about how to improve the production of the race. He consulted for six months, which turned into a year. Eventually, he took on the full-time gig of organizing the marathon.

Ciaccia said for “adrenaline junkies” like himself, he enjoys putting together a plan and watching it unfold. He also enjoys making improvements and adjustments for future races.

“It’s an ongoing process, it’s never cut and paste, it’s never that easy,” he said.

But what brings him the most joy is watching the final racer cross the finish line, whether it’s at the marathon or one of the 50 weekly races that NYRR hosts.

“I want the experience to be the best for the first to the last,” Ciaccia said. “That’s what it’s about, and that’s what this organization delivers.”

Ciaccia will pass the baton to Jim Heim, who has served as the marathon’s technical director for the last 11 years.

After nearly two decades of putting on the marathon, Ciaccia said he’ll finally be able to do things he put on hold, like reconnecting with family, traveling and, of course, running again.

“Not running an event, but running in an event,” he said. “It’s going to be fun.”